Reunion Gold Corporation

Reunion Gold Corporation

October 31, 2011 08:00 ET

Reunion Gold Announces Results From Preliminary Metallurgical Testwork From its Matthews Ridge Manganese Project

LONGUEUIL, QUEBEC--(Marketwire - Oct. 31, 2011) - Reunion Gold Corporation (TSX VENTURE:RGD) ("Reunion" or the "Company") is pleased to announce results from initial metallurgical testwork for its 100% held Matthews Ridge Manganese Project in the North West District of Guyana, South America.


  • Initial metallurgical testing of banded manganese ore from Matthews Ridge indicates that commercial product could be produced from run of mine material.

  • The testwork was focussed on the banded manganese ores, which represent the most difficult ore type to treat.

  • The objective of this initial program was to test the amenability of the ores to upgrading by modern gravity separation methods.

  • Results from the jigging tests indicate that the banded manganese ores could be upgraded to produce a saleable product grading more than 40% Mn at acceptable yields and with low deleterious elements.

A program of metallurgical testing of the Matthews Ridge manganese ores was initiated earlier this year at the laboratories of Bateman Engineering in South Africa. The ore of interest for this initial test program was the banded manganese mineralisation, a mineralisation encountered in surface trenches. A total of 700 kg each of samples labeled "low" and "high" grade ore from Matthews Ridge was sent for testing.

The "high" grade sample consisted of a blend of normal banded manganese designed to be at a grade of approximately 10-12% Mn that resembles the average grade of the banded beds encountered in the trenching at Matthews Ridge. The term "high" grade refers to the higher of the two samples tested, and is not representative of the high grade massive manganese at Matthews Ridge. The objective of this testwork was to test the amenability of a normal run of mine banded ore to gravity separation techniques, and quantify the level of deleterious elements.

The "low" grade sample was below "cut off" grade banded manganese ore (<4% Mn). The objective of testing this material was to confirm that the sub economic ore could not be upgraded to produce a commercial product.

Test results indicate that the"high" grade banded manganese ores could be upgraded to produce a saleable product grading more than 40% Mn at acceptable yields and with low deleterious elements as below:

Mn product - %Mn Mass yield - % % Fe %(Si+Al) % P
34.5 32.7 4.0 32.5 0.114
40.7 13.1 3.4 24.6 0.128
43.0 9.8 3.1 21.6 0.133

Bateman Engineering Projects: Special Projects concluded that the high grade ore supplied for testing is upgradeable by means of gravity methods to product grades at acceptable yields for all size fractions over 3 mm, whereas the -3 mm high grade material and all of the low grade material is upgradeable, but due to the low head grades and recoveries, it would probably not be economically viable to do so. The conclusions are limited to the ore supplied, and can be extended only to ore of similar characteristics.

Test objectives

The objective of this initial program was to test the amenability of the ores to upgrading by modern gravity separation methods (jigs, HMS/DMS techniques). This program will provide information and data for process design, process optimisation and product identification.Heavy Liquids Separation testing was also conducted on the fines fractions.

Description of manganese samples

Manganese mineralisation at the Matthews Ridge project has been classified in four distinct categories:

  • massive manganese which come in large high grade manganese bands that can be crushed, washed and screened to produce acceptable concentrate grades;

  • detrital or residual manganese representing discrete manganese pebbles produced from weathering and enrichment – these ores can be washed and screened to produce concentrate;

  • banded manganese representing interlayered bands of manganese and phyllites requiring crushing, washing, screening and further concentration; and

  • manganese tailings from the previous operations' wash plant consisting of minus 6mm material in the tailings basin – this material is completely deslimed and will require further treatment to produce an acceptable concentrate.

Samples sent for testwork

The samples selected and sent for testwork was the banded manganese encountered in the initial trenching programs. The samples were sent in unscreened form (-20 +0 mm), and each sample was screened separately to extract the -20 +10 (coarse) and -10 +3 mm (medium) fractions. Approximately 50 kg from each of the high and low grade bulk samples were extracted for size analysis, while the -3 mm fraction from each grade was sub-sampled for Heavy Liquids Separation (HLS) analysis.

Testwork performed

Ore samples were tested in the Bateman J-TUBE batch jig with the purpose of determining the ability to jig the ore. The Bateman J-TUBE is designed to be hydraulically similar to large scale commercial under-bed pulsed APIC jigs.

Timed batch test were undertaken on the samples, with layers extracted for density analysis and assay. Test data were fitted using the ASTRAD (Advanced Stratification Transport Rate and Diffusion) model to extract rate and quality of separation of the ore, and to provide a back-calculated approximation of the feed washability (size and density distribution of the ore) analysis.

Tests are performed for different residence times for each of the size fractions. A test campaign consists of three timed batch test, typically 1 minute, 5 minutes and 20 minutes. The longest duration test is used to determine the ultimate state of separation of the material, since the duration is long enough for the separation and re-mixing forces to reach a state of equilibrium. The two shorter duration tests produce states of incomplete separation, and this data is used in the determination of the rate and at which separation occurs, as well as the quality of separation. After each timed test, the material is extracted in layers from the top to the bottom of the bed by means of vacuum extraction. Each layer is weighed in water, oven-dried and then weighed in air in order to determine the average layer particle density. Representative samples from the layers are sent for chemical analysis.

Test results

For the sample labelled "high grade" a saleable product could potentially be produced as below:

  • For a grade of 40.6% Mnconcentrate, the yield would be approximately 13.1%, with a combined grade for silica and alumina at about 24.6% and ±3.4% Fe with phosphorous (P) at 0.128%.

  • For a grade of 43% Mnconcentrate, the yield is 9.8%, with the grades for combined alumina + silica ±21.6% and for Fe ±3.1% with phosphorous(P) at 0.133%

The detailed results are provided below. Feed rates of up to 40 tph / m width will give adequate residence time in a 3 m long jig for separation.

"High" Grade Test – Jigging Results

Yield From HG Resource %Mn %Fe %(Al+Si) %P
0.33% 50.20% 2.03% 13.16% 0.148%
3.27% 49.66% 2.11% 13.77% 0.147%
6.53% 46.36% 2.63% 17.59% 0.140%
9.80% 43.04% 3.10% 21.61% 0.133%
13.07% 40.66% 3.40% 24.57% 0.128%
16.34% 39.03% 3.60% 26.65% 0.125%
19.60% 37.85% 3.73% 28.16% 0.122%
22.87% 36.93% 3.83% 29.35% 0.120%
26.14% 36.16% 3.90% 30.37% 0.118%
29.41% 35.41% 3.95% 31.39% 0.116%
32.67% 34.59% 4.00% 32.53% 0.114%

For the "low" grade feed medium (-10+3mm) fraction, it is unlikely to upgrade to obtain a saleable concentrate product. This appears to be due to the relatively low feed grade – 2.9%Mn.

Heavy Liquid Analysis testing of the -3mm samples from both the "low" grade and "high" grade fractions gave product streams that contained gangue with low mass yields and low recoveries.


Commenting on these initial results, Mr. James Crombie, President and Chief Executive Officer of Reunion, says "We are pleased with these initial results. We wanted to test the most difficult ore type first and are satisfied we can treat the banded manganese as indicated here. We are now confident about the potential of producing high grade manganese concentrates from the blend of ores that Matthew's Ridge has to offer. Further jig testwork will be carried out in coming months on the various ore types to refine the process parameters. In addition, we will seek to have a pilot plant at our site to speed up this process".

Additional work

In addition a total of 22 samples of various ore types from Matthews Ridge have been sent to SGS Lakefield in Canada for ore characterisation analysis and QEMSCAN (Quantitative Evaluation of Materials by Scanning Electron Microscopy), a technology that can measure mineralogical variability based on chemistry at the micrometer scale. Again this will provide data for process design, optimisation and product identification. This testwork is currently underway but no results have been received to date.

Qualified Person

Bateman Engineering Projects: Special Projects,General Manager, Henk van Tonder, is a qualified person under Engineering Council of South Africa (ECSA), Professional Engineer (Pr. Eng.), reviewed and approved the content of the news release regarding the metallurgical testwork. Mr. van Tonder is a qualified person under National Instrument 43-101.

Bateman Engineering Projects: Special Projects, a world leader in advanced process models for jig design, sizing and scaling, based on batch test work, conducted the testing for Matthews Ridge ores at their Laboratories in Boksburg, South Africa under the supervision of Mr. Geoff Mann, Project Manager. The report is based on their consultant, Mr. Andrew Jonker's ASTRAD model results. The conclusions are limited to the ore supplied, and can be extended only to ore of similar characteristics.

Bateman Engineering Projects: Special Projects have an impressive reference list of over 45 Apic jig installations in most major mineral producing regions.

About the Company

The Company is a mineral exploration company focused on the acquisition, exploration and development of mineral properties in the Guyana Shield of South America. The Company,through its 100% indirectly owned subsidiary Reunion Manganese Inc.,has assembled a large, strategic land position to conduct exploration and development activities for manganese in the North West District of Guyana. The Company also has the right to acquire a 100% interest in a gold exploration project located in the Lely Mountain area in Eastern Suriname.

Manganese is the fourth largest metal consumed in the world, behind iron, aluminum and copper. It is a key component in steel and iron production with no viable substitute, and in short supply.

Additional information about the Company is available on SEDAR at and at

Forward Looking Statements

This press release contains forward-looking information. Although the Company believes in light of the experience of its officers and directors, current conditions and expected future developments and other factors that have been considered appropriate that the expectations reflected in this forward-looking information are reasonable, undue reliance should not be placed on them because the Company can give no assurance that they will prove to be correct. The reader is cautioned that the potential recoverability and grade are conceptual in nature; it is uncertain if further exploration will result in the exploration project being delineated as a mineral resource and there is no guarantee that these resources, if delineated, will be economic or sufficient to support a commercial mining operation. Until a feasibility study has been completed, there is no certainty that the commercial production will be initiated.

Forward-looking information involves known and unknown risks, uncertainties, assumptions and other factors that may cause actual results or events to differ materially from those anticipated in such forward-looking information. The forward-looking statements contained in this press release are made as of the date hereof and the Company undertakes no obligations to update publicly or revise any forward-looking statements or information, whether as a result of new information, future events or otherwise, unless so required by applicable securities laws.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this press release.

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